1. Field
The present disclosure is directed to a method and apparatus for reception of control signaling. More particularly, the present disclosure is directed to a method and apparatus for reception of control signaling at a first wireless communication device from a second wireless communication device on a wireless network.
2. Introduction
Presently, users use portable devices, otherwise known as User Equipment (UE), such as smartphones, cell phones, tablet computers, selective call receivers, and other wireless communication devices, on Long Term Evolution (LTE) networks. Users use the UEs to download files, music, e-mail messages, and other data, as well as to watch streaming video, play streaming music, play games, surf the web, and engage in other data intensive activities. Because of large amounts of downloaded data as well as large amounts of users, LTE operators can now use unlicensed spectrum to complement the bandwidth of their LTE networks to provide faster data to users. This allows the users to download data faster on their portable devices. For example, unlicensed spectrum can include spectrum at 5 GHz (e.g. used by WiFi) and other unlicensed spectrum. LTE technology can be deployed in unlicensed spectrum using the carrier aggregation framework where a primary cell uses licensed spectrum, and a secondary cell is deployed in the unlicensed spectrum. Transmissions on the unlicensed carrier frequency typically have to follow Discontinuous Transmission requirements (DCT requirements) due to regulatory requirements and due the need to co-exist with other wireless systems operating in the same spectrum, such as Wi-Fi systems, LTE devices, such as UE's, and base stations, such as Enhanced Node-B's (eNBs). In some regulations, a LTE device may also be required to perform listen-before-talk (LBT) prior to transmitting on a carrier. If the device finds that the channel is busy, then it should defer its transmission until the carrier become clear.
If a first device, such as a UE is configured with a S cell operating on unlicensed spectrum, in order to receive and decode information from physical layer signals and channels from a second device in a particular subframe on that Scell, the first device may have to take into account whether the second device has any transmissions in that subframe; and if there are transmissions, whether the transmissions in that subframe are truncated; and if the transmissions are truncated, the location of those transmissions, such as the stating or ending Frequency Division Multiplexing (OFDM) symbol of the transmission(s), within that subframe. Unfortunately, present devices do not adequately provide for reception of control signaling in such a system. Thus, there is a need for a method and apparatus for improved reception of control signaling in a wireless communication network.